The present invention relates to a catheter useable for angiographic procedures and more particularly to such a catheter which is useable for delivery of contrast media at appropriate flow rates and pressures.
Angiographic catheters are provided in four basic shapes: straight, single curve, multiple curve, and pigtail. Pigtail catheters permit an uneven distribution of rapidly injected contrast media while allowing end hole and side hole jetting. Uses for pigtail catheters include aortography, arteriography, and angiography. To introduce a pigtail catheter into a vessel a guide wire is used to straightened the catheter. The catheter is formed of a resilient material so that the catheter can resume its normal shape when the guide wire is removed.
When contrast media is ejected from a standard catheter at a high velocity, the stream of media ejected may cause damage to the artery or vein being studied. Such damage occurs when the high velocity stream displaces plaque in the vessel or perforates the vessel wall. Additionally, damage can be caused to the vessel wall by contact with the catheter tip itself, and, the catheter tip in turn may be damaged by such contact.
During high pressure injection pigtail catheters can uncoil at the tip, turning the pigtail into a hook shape, which can send a jetting stream of contrast directly at the vessel wall. Also during high pressure injection the catheter tip will flap around allowing the uncoiled tip to bash into the vessel wall violently, causing trauma.
In performing angiographic studies it is preferable to use as little contrast media as possible. This maximizes patient safety while minimizing the expense of the procedure.
It is a purpose of the present invention to provide an angiographic catheter which is capable of delivering a contrast media, at high pressure, into the vascular system while protecting the vascular system from injury.
Another object of the present invention is the provision of such a catheter which minimizes the amount of contrast media needed to complete a study.
Yet a further object of the present invention is the provision of such a catheter having a tip protected from inadvertent contact with the vessel wall.
Yet a further object of the present invention is the provision of such a catheter having all of its side ports on the inner radius of the tip curve, thus preventing the exiting contrast jet from being pressed against the artery wall, reducing any chance of contrast jet induced trauma.
Yet a further object of the present invention is that the distal tip is shaped to direct flow in an antegrade fashion, while simultaneously preventing the tip from pointing directly at a vessel side wall, reducing trauma.